I saw your comment in Shivanya's book about the nightmare thing, and I tried replying to you there. Nowadays Wattpad doesn't let readers tag each other in replies, so I came here instead. This really worked for me, and I thought you might want to try it. Look up this shloka on Google: Om Krishnaya Vasudevaya Haraye Paramatmane. If you say it a few times before sleeping, say it out loud u should be able to hear it. That's it, it truly helps. I used to have really weird, unsettling nightmares that stayed with me even after I woke up, and I've experienced exactly what you described. Even if you aren't religious, it’s worth a shot.